Convenient Tuning of the Elasticity of Self-Assembled Nano-Sized Triterpenoids to Regulate Their Biological Activities

All-Small-Molecule Supramolecular Hydrogel Combining Self-Delivery and ROS-Responsive Release for Inhibiting Tumor Growth and Postoperative Recurrence

Supramolecular hydrogels show unprecedented advantages and have attracted widespread attention in biomedical sciences. However, it is challenging for bioactive star molecules, such as celastrol, to meet ideal formation conditions. Here, we report a dynamic covalent method to construct a dihydrol-type celastrol-phenylenediboronic acid-guanosine (DHcelPBG) supramolecular hydrogel. The DHcelPBG hydrogel can effectively accelerate 4T1 cell apoptosis by modulating the PI3K/Akt signaling pathway. Especially, the DHcelPBG hydrogel can serve as a self-delivery platform for reactive oxygen species (ROS)-facilitated self-release. An excessive ROS-containing tumor microenvironment can promote the obtained DHcelPBG hydrogel to kill more 4T1 tumor cells. Meanwhile, the hydrogel also exhibits distinguished degradability and biocompatibility. Subsequently, the orthotopic 4T1 tumor model results further demonstrate that the DHcelPBG hydrogel remarkably inhibits tumor growth and does not damage healthy tissue. In the postoperative recurrence 4T1 tumor model, the DHcelPBG hydrogel also effectively prevents postoperative tumor recurrence and lung metastasis without causing adverse side effects, resulting in an extended lifetime. The DHcelPBG hydrogel also exhibits distinguished degradability and biocompatibility. The DHcelPBG hydrogel integrates ROS-responsiveness, localized self-delivery, and antitumor activity into one system for breast cancer treatment with fewer side effects, showing great potential for clinical transformation in cancer therapy.

Carrier-free nanoparticles-new strategy of improving druggability of natural products

There are abundant natural products resources and extensive clinical use experience in China. However, the active components of natural products generally have problems such as poor water solubility and low bioavailability, which limit their druggability. Carrier-free nanoparticles, such as nanocrystals, self-assembled nanoparticles, and extracellular vesicles derived from both animal and plant sources, have great application potential in improving the safety and efficacy of drugs due to their simple and flexible preparation methods, high drug loading capacity and delivery efficiency, as well as long half-life in blood circulation. It has been widely used in biomedical fields such as anti-tumor, anti-bacterial, anti-inflammatory and anti-oxidation. Therefore, based on the natural products that have been used in clinic, this review focuses on the advantages of carrier-free nanoparticles in delivering active compounds, in order to improve the delivery process of natural products in vivo and improve their draggability.

Four-pronged reversal of chemotherapy resistance by mangiferin amphiphile

Despite significant advances in diverse cancer treatment methods, chemotherapy remains the primary approach, and the development of chemoresistance is still a persistent problem during treatment. Here, we developed a derivative of the natural product mangiferin as a carrier for delivering chemotherapeutic drug, aiming to overcome drug resistance through a distinctive four-pronged strategy, including modulation of inflammatory tumor microenvironment (TME), induction of ferroptosis, deep tumor penetration, and the combinatory anticancer effects. After clarifying the promotion effects of the cancer associated fibroblasts (CAFs) in chemoresistance, and leveraging our previous elucidation of the anti-inflammatory and ferroptosis-inducing ability of mangiferin, we synthesized mangiferin amphiphile (MMF) and developed a self-assembled carrier-free nanomedicine, named MP, through the self-assembly of MMF and the representative chemotherapeutic drug paclitaxel (PTX). MP possessed a particle size of approximately 68 nm with compact filamentous nanostructures. MP demonstrated efficient tumor-targeting and deep tumor penetration abilities. Furthermore, MP effectively suppressed glutathione peroxidase 4 (GPX4) expression to induce ferroptosis, mitigated the activation of IL-6/STAT3 pathway to deactivate CAFs within the inflammatory TME, and exhibited robust anti-cancer effects against PTX-resistant breast cancer both in vitro and in vivo. This mangiferin derivative represents a promising "all-in-one" nanocarrier for delivering chemotherapeutic drugs, offering a green, safe, and convenient self-assembled carrier-free nanomedicine to effectively overcome drug resistance.

Effects of nanoparticle deformability on multiscale biotransport

Deformability is one of the critical attributes of nanoparticle (NP) drug carriers, along with size, shape, and surface properties. It affects various aspects of NP biotransport, ranging from circulation and biodistribution to interactions with biological barriers and target cells. Recent studies report additional roles of NP deformability in biotransport processes, including protein corona formation, intracellular trafficking, and organelle distribution. This review focuses on the literature published in the past five years to update our understanding of NP deformability and its effect on NP biotransport. We introduce different methods of modulating and evaluating NP deformability and showcase recent studies that compare a series of NPs in their performance in biotransport events at all levels, highlighting the consensus and disagreement of the findings. It concludes with a perspective on the intricacy of systematic investigation of NP deformability and future opportunities to advance its control toward optimal drug delivery.

Natural Products from Herbal Medicine Self-Assemble into Advanced Bioactive Materials

Novel biomaterials are becoming more crucial in treating human diseases. However, many materials require complex artificial modifications and synthesis, leading to potential difficulties in preparation, side effects, and clinical translation. Recently, significant progress has been achieved in terms of direct self-assembly of natural products from herbal medicine (NPHM), an important source for novel medications, resulting in a wide range of bioactive supramolecular materials including gels, and nanoparticles. The NPHM-based supramolecular bioactive materials are produced from renewable resources, are simple to prepare, and have demonstrated multi-functionality including slow-release, smart-responsive release, and especially possess powerful biological effects to treat various diseases. In this review, NPHM-based supramolecular bioactive materials have been revealed as an emerging, revolutionary, and promising strategy. The development, advantages, and limitations of NPHM, as well as the advantageous position of NPHM-based materials, are first reviewed. Subsequently, a systematic and comprehensive analysis of the self-assembly strategies specific to seven major classes of NPHM is highlighted. Insights into the influence of NPHM structural features on the formation of supramolecular materials are also provided. Finally, the drivers and preparations are summarized, emphasizing the biomedical applications, future scientific challenges, and opportunities, with the hope of igniting inspiration for future research and applications.

The Inhibitory Impact of a Co-Assembly Gel with Natural Carrier-Free Binary Small Molecules, as Used in Traditional Chinese Medicine, on the Viability of SW1990 Cells

Chinese herbs are a huge treasure trove of natural products and an important source of many active molecules. The theory of traditional Chinese medicine compatibility (TCMC) is widely applied in clinical practice, but its mechanism is still ambiguous. This study aims to open a new window for this predicament by studying the interaction between the main active ingredients from a drug pair. Carrier-free assembly of natural products improves the shortcomings of traditional nanodelivery systems and opens a new path for the development of new nanomaterials. The drug pair "Pueraria and Hedyotis diffusa" has been commonly used in clinical practice, with a predominant therapeutic effect. This study is devoted to the study of the binary small molecule co-assembly of the main active molecules from the drug pair. In this study, we introduce a carrier-free composite gel, formed by the co-assembly of puerarin (PUE) and deacetylasperulosidic acid (DAA) via non-covalent bonds including π-π packing, intermolecular hydrogen bonding, and C=O π interactions. With a strain point 7-fold higher than that of P gel, the P - D gel exhibited favorable rheological properties. The survival rate of SW1990 cells in the P - D group was only 21.39% when the concentration of administration reached 200 μM. It thus demonstrated activity in inhibiting SW1990 cells' survival, suggesting potential in combating pancreatic cancer. Furthermore, this research offers a valuable concept for enhancing the mechanical properties and bioactivity of hydrogel materials through the utilization of a multi-component natural small molecule co-assembly approach. More importantly, this provides new ideas and methods for the treatment of pancreatic cancer and the analysis of traditional Chinese medicine compatibility theory.

A carrier-free tri-component nanoreactor for multi-pronged synergistic cancer therapy

Non-invasive therapies such as photodynamic therapy (PDT) and chemodynamic therapy (CDT) have received wide attention due to their low toxicity and side effects, but their efficacy is limited by the tumor microenvironment (TME), and monotherapy cannot achieve satisfactory efficacy. In this work, a multifunctional nanoparticle co-assembled from oleanolic acid (OA), chlorin e6 (Ce6) and hemin was developed. The as-constructed nanoparticle named OCH with diameters of around 130 nm possessed good biostability, pH/GSH dual-responsive drug release properties, and remarkable cellular internalization and tumor accumulation capabilities. OCH exhibited prominent catalytic activities to generate •OH, deplete GSH, and produce O2 to overcome the hypoxia TME, thus potentiating the photodynamic and chemodynamic effect. In addition, OCH can induce the occurrence of ferroptosis in both ferroptosis-sensitive and ferroptosis-resistant cancer cells. The multi-pronged effects of OCH including hypoxia alleviation, GSH depletion, ferroptosis induction, CDT and PDT effects jointly facilitate excellent anticancer effects in vitro and in vivo. Hence, this work will advance the development of safe and effective clinically transformable nanomedicine by employing clinically-applied agents to form drug combinations for efficient multi-pronged combination cancer therapy.

A novel nonreversible heat-induced low-molecular-weight gel based on naturally-occurring self-assembled fupenzic acid for tumor therapy

Herein, a nonreversible heat-induced supramolecular gel based on natural products was reported for the first time. This natural triterpenoid, fupenzic acid (FA), isolated from the roots of Rosa laevigata, was discovered to be capable of forming supramolecular gel spontaneously in 50 % ethanol-water solution induced by heating. Distinguished from the common thermosensitive gels, the FA-gel showed a distinctive nonreversible phase transition from the liquid to gel state upon heating. In this work, the entire gelation process of FA-gel induced by heating was recorded digitally by microrheology monitor. And a unique heat-induced gelation mechanism based on self-assembled FA has been proposed by using various experimental methods and molecular dynamics (MD) simulation. Its excellent injectability and stability were also demonstrated. Furthermore, the FA-gel had been evaluated to exhibit better anti-tumor activity and higher biosafety comparing with its equivalent free-drug, which opened up a new possibility to reinforce antitumor efficacy by using natural product gelator originated from traditional Chinese medicine (TCM) without any complicated chemical modifications.

Photosensitizers Dispersed on Nanosized Triterpenoid Matrix with Deaggregation-Enhanced Singlet Oxygen Production

Aggregation-caused quenching (ACQ) effects of photosensitizers severely cut down the generation of quantum yield of singlet oxygen (¹O₂) for effective photodynamic therapy (PDT). Herein, we accomplish a deaggregation-enhanced ¹O₂ production strategy by the noncovalent coordination of a clinically applied triterpenoid oleanolic acid (OA) and hematoporphyrin (Hp) via one-step self-assembly, forming a nanosensitizer OH, in which Hp is interspersed on the surface of the OA matrix in a face-to-face manner. The scattered arrangement of Hp held by the OA matrix decreases the π-π aggregation in Hp, leading to a 3.7-fold boost in the intracellular ¹O₂ yield and high phototoxicity in vitro and in vivo. Moreover, the biologically active OA enables OH to display excellent cellular uptake efficiency (increase by 36-fold), deep tumor penetration, and synergistic antitumor outcome at a low dose. Thus, this simple strategy paves the way for the green development of efficient photosensitizers.

Facile preparation of Au- and BODIPY-grafted lipid nanoparticles for synergized photothermal therapy

Gold nanoparticles with large size exhibit preferable properties for photothermal therapy (PTT). However, the prolonged tissue retention and slow elimination of gold nanoparticles limit their therapeutic applications. Previously, gold nanoclusters carrying lipid nanoparticles (Au-LNPs) have been reported after simply mixing Au³⁺ with preformed diethylenetriaminepentaacetic acid lipid nanoparticles to solve this contradiction. Au-LNPs demonstrated enhanced photothermal effects in comparison to neat gold nanoparticles. To further improve the photothermal activity, we introduced the organic photothermal agent boron dipyrromethene (BODIPY) to Au-LNPs for synergistic PTT. Au- and BODIPY-grafted LNPs (AB-LNPs) were formed by simply mixing Au-LNPs with BODIPY. The BODIPY could be associated stably to Au-LNPs, and the release of BODIPY from AB-LNPs could be accelerated by laser irradiation. AB-LNPs are scalable and showed excellent photothermal effects. AB-LNPs showed enhanced cellular uptake efficiency compared to free BODIPY in 4T1 breast cancer cells. Under laser irradiation, AB-LNPs exhibited synergistic photothermal effects with significantly reduced dosage compared to monotherapy (treatments with Au-LNPs or free BODIPY alone). This study thus provides a facile and adaptive strategy for the development of a scalable and safe high-performance nanoplatform for synergistic PTT in the treatment of cancer and other diseases.